California bullfrog (New Pleistocene)
Notable amount of following information for the species is compiled by using information from animaldiversity.org site. The link to the original species article is here. California bullfrog (Lithobates catesbeianus californicus) - A subspecies of American bullfrog and is descendant of invasive populations of American bullfrogs that were introduced to California due to pet trade and food. It is very similar to its ancestors, but is slightly larger and more brighter in color. Biology and reproduction California bullfrog has a notable brighter yellow shade to it's skin than that of an American bullfrog. A notable pattern on it's back are the 6 nail-shaped spots. It's speculated that these are the same 3 spots tadpole C. bullfrogs wear on their dorsal fin. As the tadpole ages, the fin recedes but in a specific way, it's bottom part divides in the middle and the resulting halves slide away from each other to fuse with the backside, forming not 3, but 6 spots as a whole. C. bullfrog is said to have a bit more pointier protruding ankles and males have throats that have turned from yellow to orange. The typanum (not pictured) located on either side of the frog's head have not increased in size but still looks shrunken due to the bullfrog itself had grown throughout the millions of years. The grey spot on C.bullfrog's forehead is said to slightly reflect rainbow-like glint, to confuse predators for a second but it only works during sunny weather. Fertilization resembles that of the American Bullfrog by females depositioning nearly 20 000 eggs coated in film in calm waters which are fertilized by a single male, who due to it's territorial behavior has scared other males out of the particular territory within whom the eggs been laid. Tadpoles can take care of themselves though they sustain themselves with yolk at first. Behavior and ecology When not in a mood for reproducing, an adult California bullfrog prefers to sit and wait for prey to come to snatch it with their tongues. Like lots of frogs they have much easier time perceiving moving prey than slow moving prey. C. bullfrog dislikes colder weather and builds a small mud cave for itself. Adult C.bullfrog males can take over territories up to 30 meters and physically wrestle each other. Tadpoles and females have much shyer behavior and merely observe a stranger from afar before continuing moving in the direction they were heading. Male bullfrogs can perform "jug-o-rum" rumble like their ancestors could but due to their body size to tympanum size ratio it isn't as loud as it was in the past. C. bullfrog tadpoles are herbivores, but become predatory in adulthood as well as cannibalistic. They are in turn eaten by birds, reptiles and mammals of the California river biome, though fish avoid tadpoles since they taste foul which also used to be a trait of ancestral American bullfrog tadpoles. C.bullfrog can also distribute very mild toxins from it's skin. Curiously these toxins, when diluted with the river's water, can slightly cure skin ailments and limit ectoparasite activity which is why animals who are around the size of C.bullfrog will sometimes roam into the bullfrog's riverside territory to feel relieved. However it is risky, because C.bullfrog can try fighting like-sized invaders or eat those who are slightly smaller. Evolution The American bullfrogs which were introduced into California via pet trade and food cargo, proved to have upper edge on lots of local frog species. American bullfrogs were proved by humans to have underwent an evolution in even more distant past by being exposed to diverse aquatic predator fauna which they managed to survive and develop useful tactics, like tadpoles which limit their activity during different times of day which ensures that at least some stay hidden during danger. Having already been accustomed to river biomes, American bullfrog started colonizing the newly formed Californian River. Due to the different surroundings it's skin colour gradually changed and it was able to obtain larger amounts of food making it grow. It skin becoming brighter could be associated with the fact that A.bullfrog started spending large amounts of time sitting around in the shallow, being surrounded by the reflective water surface. With all the reflectiveness around it, the bullfrog could afford acquiring a skin color that's more reflective as well. Category:Alternative Evolution Category:New Pleistocene Category:California Category:Amphibians